The industrial finishing of hardcover books is predominantly carried out on book production lines on which book blocks are each combined with an associated book cover to produce finished books. During so-called casing in, i.e. when the book cover is bonded to the book block, the exact joining of their edges is crucial for a harmonious binding. Therefore, the prior adjustment and, if necessary, shaping of the central region of the book cover, i.e. the spine region, which receives the spine of the book block in the finished book, is of importance for a high quality of book. Of similar importance is the shaping of the folding regions of the book cover which directly adjoin the central region on either side and later constitute the opening hinges of the finished book. The requirements for the shaping of the book cover, which is carried out under the effect of heat in each case, and therefore for the shaping tool used for this purpose differ according to whether the finished book has a rounded or angular spine and according to the form of the rounding and according to the thickness of the book. Accordingly, the shaping tools must be designed so as to be adjustable and/or interchangeable.
A book binding machine comprising a casing-in apparatus is known from DE1436086 A, in which the book cover is conveyed from a magazine into a shaping station. There, the spine region of the book cover is first rounded by a shaping tool. In order to form the folding regions separating the spine region from the lateral boards of the book cover, two fold-forming rails are guided in opposite directions at least as far as the book cover while the shaping tool is being raised. This procedure, which is only described in very general terms in DE1436086 A, can be seen in more detail in DE19853254 A1, which describes a device for rounding book covers. Therein, the spine region of the book cover is pressed against an elastically deformable supporting surface by means of a heated shaping tool designed according to the shape of the book block. In the process, the spine region is rounded and the pressed-in folding regions are made flexible. Normally, the shaping tools are kept available in conventional shape-dependent tiers and when the spine shape of the book cover or the thickness category of the associated book block changes, they are swapped over. Accordingly, the production of books with different thicknesses requires keeping a large number of corresponding shaping tools available, which causes relatively high costs for the shaping tools and thus also for the entire device for shaping book covers.
Moreover, the manual changeover of the shaping tools that is required for this purpose increases the time it takes to set up the machine. Ultimately, the newly inserted shaping tools are not yet at an operating temperature and must therefore first be heated up after their installation.
An apparatus for shaping book covers for books having straight spines is known from EP2325020 A1. The shaping tool of said apparatus, which is interchangeable depending on the thickness category of the books to be produced in each case, has two shaping rails which stand vertically, are spaced apart from one another and each rest on a tool beam by means of a base rail. The shaping rails are arranged in an initial position below and apart from the book cover, which is initially still in an outstretched position. In order to form the folding regions of the book cover provided on either side of the spine region, the shaping rails are raised together with their tool beam against counter shaping rails arranged thereabove. To shape the book cover, heat is applied via the shaping tools. For this purpose, the tool beam carrying the shaping tool rests on an intermediate element which is designed as a heating element and is equipped with heating rods. The shaping tool is both brought up to an operating temperature and kept at this temperature by the heating element.
The shaping rails are each coupled to two catches, which are spaced apart from one another in their longitudinal extension, are rotatably driven eccentrically about a vertical axis and are guided in the tool beam, in a guide plane by means of their respective base rails. The spacing between the two support rails and therefore the width of the spine region of the book cover can be adjusted within a certain thickness category by an adjustment of the catches achieved by means of a common drive. In the process, the actuating power is introduced into the tool beam by means of an actuating mechanism arranged therebelow. An actuator is arranged in parallel with a longitudinal axis of the shaping tool.
EP2923852 A2 likewise relates to a device for shaping book covers. In addition to a first shaping tool for book covers which are intended for book blocks having straight spines, a second shaping tool is disclosed for book covers which are suitable for book blocks having round spines. Using the second shaping tool, the spine region of a book cover can be rounded while it is being raised from its outstretched position, it being possible to produce different formats and contours of the spine region. For this purpose, this shaping tool has a base element in which a first shaping element is movably arranged. In the process, in the event of a longitudinal movement of the first shaping element, the elevation of said first shaping element can also be changed relative to the base element by means of a ramp-like guide. In the same manner, a second shaping element is arranged in the first shaping element such that both shaping elements can be adjusted towards one another or towards the base element in a vertical plane relative to the flat outstretched book cover. Within a particular thickness category of spine regions, both the width and the curvature of the spine region of book covers to be processed after one another can thus be shaped differently as required without changing over the shaping tools.